This invention relates to a data recording medium such as an optical disk on which data is recorded or from which recorded data is reproduced, a data recording method for recording data on the recording medium, and a data reproducing method for reproducing data recorded on the data recording medium.
Conventionally, an optical disk apparatus for recording data on an optical disk having recording tracks or reproducing data recorded on the optical disk by use of laser light output from a semiconductor laser oscillator mounted on an optical head is put into practice.
With the above optical disk apparatus, data is recorded in the ECC block unit including a plurality of sectors on the optical disk.
With the above optical disk apparatus, an error in the sector unit, that is, a defective sector is detected and data is recorded or reproduced while skipping the defective sector.
Data on the defective sector is collectively recorded in the defect management area at the end of the data recording process.
Therefore, when the power supply is turned OFF in the course of continuously recording data such as moving pictures, data on the defective sector is not recorded on the optical disk and proper measure cannot be taken for the defect later.
An object of this invention is to provide a data recording medium, data recording method and data reproducing method capable of detecting the defect position later and taking proper measure later when the power supply is turned OFF in the course of continuously recording data such as moving pictures.
According to one aspect of this invention, the above object can be attained by a data recording medium which has tracks in a concentric or spiral form into which data is recorded and in which a format including groups of a plurality of successive sector fields each including an address field having a preset track length for previously recording address data indicating the position on the track and a data recording field for recording record data is defined and data is recorded in a block field unit which has a set of preset number of sector fields among said plurality of sector fields, comprising:
a defective portion searching data recording field into which data for searching for a defective portion is recorded in the data recording field of the sector field unit.
According to another aspect of this invention, the above object can be attained by a method of recording data on a data recording medium which has tracks in a concentric or spiral form into which data is recorded and in which a format including groups of a plurality of successive sector fields each including an address field having a preset track length for previously recording address data indicating the position on the track and a data recording field for recording record data is defined and data is recorded in a block field unit which has a set of preset number of sector fields among said plurality of sector fields, said method comprising the step of:
recording record data in sector fields other than a sector field containing a defect, recording record data and recording data used for searching for a defective portion into a data field of each sector field unit in a sector field free of a defect when record data are sequentially recorded into the block fields on said data recording medium.
According to still another aspect of this invention, the above object can be attained by a method of recording data on a data recording medium which has tracks in a concentric or spiral form into which data is recorded and in which a format including groups of a plurality of successive sector fields each including an address field having a preset track length for previously recording address data indicating the position on the track and a data recording field for recording record data is defined and data is recorded in a block field unit including an error correction data recording field which has a set of preset number of sector fields among said plurality of sector fields and in which error correction data for reproducing record data recorded in said preset number of sector fields is collectively recorded for the set of said preset number of sector fields, said method comprising the steps of:
skipping a sector field containing a defect in a block field unit, recording record data and error correction data into a next block field and recording data used for searching for a defective portion into a data field of each sector field unit when record data and error correction data are sequentially recorded into the block fields on said data recording medium;
recording the data used for searching for the defective portion in the data field of each of the sector field units of the next block field.
According to another aspect of this invention, the above object can be attained by a method of reproducing data recorded on a data recording medium which has tracks in a concentric or spiral form into which data is recorded and in which a format including groups of a plurality of successive sector fields each including an address field having a preset track length for previously recording address data indicating the position on the track and a data recording field for recording record data is defined and data is recorded in a block field unit including an error correction data recording field which has a set of preset number of sector fields among said plurality of sector fields and in which error correction data for reproducing record data recorded in said preset number of sector fields is collectively recorded for the set of said preset number of sector fields, said method comprising the steps of:
detecting an interruption of recording when said data recording medium is loaded;
sequentially reading data for searching for defective portions recorded in the data field of each sector field;
determining whether each data field includes a defective portion, from data for searching for defective portions thus read; and
reproducing data recorded in the data recording field based on the result of determination of the determining.
According to another aspect of this invention, the above object can be attained by a method of recording data on a data recording medium in units of one sector such that the data is recorded in a recording field specified externally, said method comprising the steps of:
first step for inputting a recording start position of data, recording end position of data, recording size of data, and data to be recorded; and
second step for recording data input from the first step into a portion between the recording start position and a recording end position which is newly determined so that said portion has a recording capacity greater than the data recording size input in the first step by an amount corresponding to a preset number of sectors.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.